1) Mix all dry ingredients in a large bowl.
2) Mix skim milk, pumpkin, egg, and vanilla extract in a smaller bowl and add to the dry ingredients. Use a rubber spatula to make sure all ingredients are blended together but do not overmix.
3) Heat waffle iron until the indicator light comes on signaling it's ready.
4) Ladle approximately 1/4 of the batter into the center of each waffle well.
5) Cook until your waffle iron indicates that the waffles are ready, or until steam stops coming out of the sides of the waffle iron, about 4 to 5 minutes. If you like crispier waffles than I do: keep 'em in the waffle iron for a bit longer than I do.
6) Open the waffle iron and carefully lift the edge of each waffle with a fork to remove the waffles from the waffle iron.
7)Serve immediately or cool and refrigerate or freeze for later. Pop in the toaster to crisp them up right before serving, if desired.